McLaren will remove the F-duct from its car for the first time this season at the Italian Grand Prix, AUTOSPORT has learned, with the low downforce nature of the circuit negating any benefit the system brings.
The Woking-based team was the pioneer of the F-duct at the start of this year, and the design has proved such a success that all its main rivals have copied the idea. Renault will be the latest to introduce it at this weekend's Belgian Grand Prix.
The F-duct helps provides a straightline speed boost by allowing the drivers to stall the rear wing on the straights - and teams can use it for a simple top-speed advantage or to help them run more downforce in the corners without suffering a drag penalty on the straights.
Although Monza has the highest top speeds of the season - so would in theory be perfect for a straightline advantage - the fact the track requires such a low wing set-up actually makes the F-duct redundant because there is not enough drag for it to get rid of.
McLaren's decision to remove its F-duct for the Italian Grand Prix is likely to become standard practice, with all teams instead set to focus on a low-downforce aerodynamic package better suited to the Monza layout.
All teams had been expected to remove the F-duct at the Monaco Grand Prix earlier this year, but McLaren elected to keep it on its car then - saying at the time that there was no alternative.
"F-duct is something which will work better on the long straight than a circuit like this," McLaren team principal Martin Whitmarsh said in Monaco. "It is a standard part of our car. We don't have a non F-duct variety to fit in any case."